lyman



3 Sheets-Sheet 1 A. S. LYMAN.

AIR ENGINE.

No. 10,576. Patented Feb. 28, 1854.

3 SheetsSheet 2.

AS. LYMAN.

AIR ENGINE. No. 10,576.

Patented F915. 28, 1854.

3 Sheets-Sheet 3.

A. s. LYMA'N,

AIR ENGINE.

No. 10,576. Patented Feb. 28, 1854.

A. s. LYMAN,,OF YORK, N. ,Y.

AIR-ENGINE.

Specification of Letters Patent No.

ToaZZ whom it may concern Be it known that I, A. S. LYMAN, of the city,county, and State of New York, have invented new and useful improvementsin engines for generating power by means of the expansive force derivedfrom heated air and gases, also by means of the expansive force ofliquid carbonic acid and other ex-' pansible liquids; and I do herebydeclare that the following is a full, clear, and exact description ofthe principles of my invention and of the construct-ion andoperation ofthe same, reference'being had to the accompanying drawings, making apart of this f specification. v v In order that the nature and extent ofmy improvements may be readily understood, I will begin by statingwherein my engine 1 resembles Sterlings air engine and wherein;

it differs from that and from all others in? use; It resemblesSt-erlings engine in the; fact that two strong vertical, and nearly; airtight cylinders, called generating cylinders, are connected, one witheach end of working cylinder, in which a piston movesi in theusualmanner. Each of these generat- 1 ing cylinders contains vagenerating plunger,, which moves up and down, for the purpose; ofdisplacing the air. When this plunger} is at one end of. the generatingcylinder thel air is at the other, and as one end of this! cylinder iskept at a high temperature and the other cold, as is practicable, whenthe; air is brought to the hot end it has its tem-,

perature and pressure increased; when it is brought to the cold end itsheat and pressure? are diminished. VVhile moving from one end of thegenerating cylinder to the other,

it passes through a multitude of narrow vend of the working cylinder tothe other.

There were, however, several serious defects in Sterlings engine, whichprevented its general introduction, and these defects are common to allother high pressure air engines with which I am acquainted.

10,576, dated February 28, 1854 A great obstacle to the success ofSterl' ingsor other air engines has been their liab hty to leak when ahigh pressure has been attempted. This difficulty has been so great asto render it not only impracticable to attempt the use ofair under avery great pressure, but utterly impossible to use carbonic acid "in aliquid state, which expands and contracts by given changes oftemperature three or four times as much as air, and for other reasons isbelieved -to be moreeconomical. But in my improved apparatus so long asthere is aproper supply nothing but water or oilcan, in any case, leakout, or escape,

or metal. Even when charged with liquid carbonic acid, under one hundred*atmos pheres pressure, the acid would not tend to leak through its caseany more than the same amount of water would under the pressure of oneatmosphere 0nly.. j-

Another obstacle to the success of air engines, which is often said tobeinsurmountfrom any joint, or through thepores of iron sojf able, is theburning out of thejheatingsurface. But in this ap'paratusgthe heat isapplied through the medium of water, or

other suitable liquid, and it is not possible to overheat so as to burnthe metal. f:

.Another difliculty in the way of'the success of air engines hasresulted from the nature of the fluid used in them. IWhi le steam 1s alubricator, hot air generates fridtion, and rapidly destroysthe,cylinder and packing. To avoid thisdestruction"and-- wasteof power,more particularlythe leak-s caused by it, some have used the air from pthe cold end of the generating cylinder, but this has always been doneatthe expense of a large amount of fuel wasted. In case the air was soheated as to double, its tension, it 7 would require twice ,as muchfuel-when the working cylinder wassupplied from the cold end aswhensupplied f r om-the hot 'endof the generating cylinder. In myimproved engine, the whole ,wo'rking cylinder i's'fillecl with water,and the generating cylinders also, except the r upper ends, whichareo'ccupiecl by Lthei'hOtair chambers, theheat repositories, and thegenerating plungers,

and the hot air chamberis enlarged, as the piston recedes from it, so:that all ,the air is kept hot, the piston is in effect driven with hot,ial though the working c-ylinder is Lilli 6f coldwater, 7 Again, it isvery common remark with authors'on steam and the Steam Engine Gr.Renwick,

page 251) that the maximum performance of the low pressure engine takesplace when I UNITED STATESPATENT OFFICE.

the Velocity of the piston is from 250 to 280 feet per minute,because'the whole tension of the steam acts as a pressure on the pistononly; when that is at rest and with every increaseof velocity, thepressure must be diminished. The above remark is probably correct, asapplied to the ordinary steam engine, or to any of the forms of airengines that have been made public, for it is a common and a veryserious defect with all of them that they pass the steam or air throughcontracted pipes between the'boiler or generator and the workingcylinder. These passages being only from to the area of the cylinder,the air or steam must pass through them from 10 to 30 times as rapidlyas the piston of the engine moves. That is, when the piston of theengine travels 250 or 280 feet per minute the steam or air must movefrom 2500 to 8000 feet per minute in its passage to the workingcylinder. 1

My fourth, improvement consists in combining the generating cylinderswith the opposite ends of the working cylinder di- .rect, and dispensingwith these contracted pipes, by making the passages as large as theworking cylinder in area, so that the piston may be driven as fast asthe motive power moves, without the loss of power from the abovementioned cause.

A fifth source of loss has resulted from the application of the heat tothe lower end of the generating cylinder, while, at the 85 same time,the attempt has been made to keep the upper end of thiscylinder cold bythe application of cold water upon it. But air being heated its specificgravity is lessened, and it rises, and currents are formed 10 of hot airrising from the lower or heated end through the heat restorer into thecold part, while currents of cold air flow clownward. The heater andcooler thus each tend to neutralize the effect of the other.

improved engine, I apply the heat in the upper part of thegeneratingcylinder and the cooling fluid in the lower part, so that 'while theheated air rises, and the cold air falls, it does not tend to destroythe effect of theheat restorer, but rather to .render it more perfect.

A sixth source of loss has arisen from the fact that the heat restorer,as commonly Composed made, has been very defective. principally ofmetal,.it hasconducted the heat from the hot to the cold side. When madeof sheets of metal separated by nonconducting substances, it did notallow free passage for the air. In my improved engine, I use glass tubesand rods, from the size of ahair upward, standing vertical and parallel,the air passing through them length- -wise, the upper end being hot andthe lower end cold. As glass is a very bad conductor, the heat is not somuch conducted down- In my ward by it, and fuel is thus saved that waswasted by the other plans, While at the same time the air, liquidcarbonic acid, or other fluid passes more freely through this heatrestorer than through those ordinarily in use.

Plate 1, is a horizontal plan of my improved engine. Plate 2, is a sideview. Plate 3, shows the sections. Plate 4, is a vertical section on alarger scale, showing more clearly the internal arrangement.

Plate 3. Figure 1, representsa vertical longitudinal section, throughthe principal parts. Fig. 2, is an end view of some partswith a sectionof others. Fig. 3, is a horizontal section through one cylinder, atJD, D(Fig. 1), and through the other at D, D";

heating tubes and one of the series of cooling tubes. Fig. 4, is asection through the rocking shafts and their appendages. Fig. 5, is anend view.

Similar letters of reference indicate corresponding parts in each of theseveral figures.

A, A, A, A, the generating cylinders; B,

working cylinder; J, the working piston in i this cylinder; E, E, thegenerating plungers moved up and down in the generating cylinders by F,F, the plunger rods, with their lower ends toothed to correspond with,and receive the teeth of G, the toothed segments which, by their partialrevolutions, raise and 6, b, b, b, &c., is a also a horizontal plan ofone of the series of i a a represents ing the lower flanges in the samemanner .and surrounded by cold water; 0, 0, 0, c, a

cap attached to the outer edges of the upper flanges by an air tightoint.

n, n, represent the short cylinder connecting the middle flanges attheir outeredges, and together with these flanges and the inner cylinderforming a chamber which has no openings, except by the heating tubes,

0, C, and the cooling tubes, C", C"; a, a, the heat repository, or heatrestorer, (called by Ericsson the regenerator). This consists of a greatnumber of glass, rods and tubes, from the size of a hair upward,standing vertical and prevented from falling into the tubes by a fewsheets of wire gauze, upon which the glass tubes and rods rest. Glassbeing a very bad conductor of'heat', the tubes and rods may be short,and although their upper ends may remain at a hig'htemthis regeneratorthan-through the same, distion,

tance of wire gauze. B, B, a short'cyli'nder extending down from thelower flange, an forming with it 'andthe inner cylinder the cold airchamber; F, F, a flange extending out a short distance fromthe cylinder,in-. closing-the heat repositories, for the pur-f pose of supporting theheat repositories, the

heating tubes, (0), and the coolingtubes,

((1), whichzare 'all connected "together,

This flange:.-restsF-upon the-outer case, ;or generating cylinder, (A,A) There are also small openings through this flange vertically, for thepurpose of' allowing the free passage of the water,-or othen-liquid, upand down between the external strong. iron cylinder, for sustaining thepressure, and

the internalithin copper cylinder for con- I p cam is such that thegenerating plunger taining theiair. 'm,'m, rings offload conductingmaterial, introduced between the flanges of theupper and lower or thehot and coldparts of the outer case. The case is divided at thatspo'int,and separated, by bad conducting material, for the purpose ofpreventlngwas'te of-fuel,.that would otherwise occur. 25, ?3, smallscrew'plugs for the purpose of letting out the air from the :narrowspace between thestrong outer case and the internal coppercylinders andtubes,v containing-theY-a1r.- s Fig. 2 X, is the passage between thegen-; erating cylinder and the working cylinder. The area, of this.passage isasilarge as that of the working cylinder. 1, is;the pistonrod.' I 1:;

Figs. 1 and 4:, R, is the square link arm, with a sliding box, -23, inthe link, through the center-of, which the pin S, is fixed, serv ing asthe connecting pin forzthe connecting rod from the cam frame, P, toP, P,P,, are the guides to the cam frame, moving in the brass boxes which areshown in ajsecwith a plan of a part ofthe cam frame, N, is a cam 1'01'1the-shaft, M. N, is the other cam in -its relative position to; the cam,N, to produce a proper movement of thegenerating plungers, (b), (b). 1

Fig. '2: A, is the box in wh' h the toothed segment, G, Fig. 1, isworked; S, i the shaft, 'andG, thearm,-by, means ofwhich this segment isworked. G, G, are. caps. to the shifting boxes, inwhich the shaft, S, ofthe toothed segment rolls. g?

Figs. 3 {and 5: H- S, S,S, H, arethe hot water circulating tubes,thedirectionof the currents represented by the arrows. C, S, S, S, C arethe cold water circulating tubes. The furnace under the hot water tubesand the box containing the reservoir of cold water surrounding therefrigerating tubes are not shown.

piston-recedes from it and the air Fig. 4: S, is the; small rockingshaft, to whichthe link -arm,'R,-1, and the rocking;

{arms,R,l, and R, 1, areattached. S,;is

a vshaft whichturns' around the surface-of the: shaft, S, and to whichare keyed, thelink arm, R,'2, and-the rocker arms, R, f2, d ,R,,2.' (Z,(Z,

1 shaft moves.

are boxes in which theinner O, 2,and 0,1, are lifting rods attached tothe block, 25, Fig. 1, which *p lSS and move vertically? through holes"bored, {through bot-h shafts, in line with the center iof the linkblocks, and oftheir respective, rocker arm connecting pinsyr, 1'.The'lower. fends of the lifting rods, marked, 2 and 1,. are slotted in'a link which is at right angles and in the same plane with the vertical'links, R, 1, and R, 2. A pin-attached to the end of a lifting arm,worksin these small limbs, 2 and 1, by which the generatving plungersstroke.

aregiven a-full' or partlof a It will beperceived that the form will bebrought from the lowest to the highest point of its movement in theshortest practicable space; and consequently the air. in, that cylinderwill be cooled in theshort est practical time. It will also. beseenthat;

the form of thecam is such that the generating plunger will be broughdown about, two thirds of its stroke in,this case in the. shortestpracticable time, when it will mofve slowly, so that the hot air chambershall.

be enlarged only .asfast as the-working shall not expand down throughthe cooler. Byfthusf gradually enlarging the hot air chamber, during theentire stroke of the piston,itilis" evident, that a great saving offuelmaybe effected;

. Directions for charging the ertiqz' rw. Tubes leading from. a commonreservoir (not: shown) connect w th thelower part of'leach of thegenerating cylinders through self- .acting valv es;w That separatereservoir is. I charged to any desired pressure, andtheairf permltted toescape freely into both of the generating cylinders through thesevalves. They are consequently uniformly charged withthe same pressurewhen the air. is of the same temperature in each, if theengin isinoperation. 1 If it is desired to'chargewith air to a pressure of 600lbs. perIinch,

we first charge the whole working and gen erating cylinders with apressure of 2001 lbs.- We' thenforce 1n water-until the whole ap-lparat-us is'about two-thirds full; Thiswater is easily pumped .inunder apressure of.,50'0 or 800 lbs, and itc'ompresses nearly all the air upunder 'the internal copper cylinder.

Iioos'en the small screw plugat the top ofv I the outer case until theair contained between the'internal copper cylinder andthe outer case hasall escaped by it. When; the .water.

, begins to escape from the plug, itlis tight-Z ened. Small plugs arealso loosened at the highest point of the circulating tubes of therefrigerator and the air permitted to escape. WVe have here threecylinders surrounding the air or other driving power. 1st. The thincopper cylinder. This cylinder is open only at the bottom, and the air,from its less specific gravity, remains in it. 2d. The cylinder of watersurrounding this copper cylinder and completely lining the outer case.-

3d. The strong outer case. -Now it is plain that nothing but water canleak from the outer case, for nothing but water comes in contact with itinside, solong as there is 7 sufficient in the engine to prevent the airor other driving fluid from expanding, so as to more than fill the innercopper cylinder, and

ner cap, between it and the outer iron case.

On being heated, this water, and that in the coil, expands, and a smallquantity passes down through the holes in the flange F, Plate 4:,supporting the internal copper cylinder tubes, etc., and forcing thecold water, before it compresses the air or other driving power, stillhigher up under the inner cylinder.

The operation is as follows: Whenthe engine is started by moving thestarting bar,

so as to bring the generating plunger nearest to the working pistondownward, then the air which is in the cooling tubes, C", and in thespace, (0), below them will rush up through the heat restorer andthrough the heating tubes, C, and occupy the space above the plunger, 6,b. The space in the cooling tubes, C, and below them first occupied bythe air is now filled with the cold water displaced by the generatingplunger in its downward movement, The air in passing through the upperpart of the heat restorer and the heating tubes, C, is heated, andconsequently expanded. The same movement of the starting bar that bringsone generating plunger down and heats the air raises the othergenerating plunger and forces the air above it, down through the heatingtubes, C, the heat repository, a, where it leaves most of its heat, intothe cooling tubes, C, and the chamber, (C), below. This air isconsequently cooled and condensed. The air being thus suddenly expandedin the space back of the piston and condensed in front of it, the pistonis forced to the other end of the cylinder, when, by the movement of thecams, the position of the generating plunger is reversed and thepressure transferred to the other side of the piston, and thus thereciprocating motion is produced.

What I claim as new, and desire tosecure by Letters Patent, is

1. The'mode of preventingthe waste of the compressed air, liquidcarbonic acid, or other driving power, by interposing between it and theoute'r cylinder of the engine, a reservoir of water, or other suitableliquid, substantially in the manner described.

2. I claim the mode of applying the heat to the generating power,through the agency of water, or other liquid, in the mannersubstantially as specified; thus avoiding. the possibility of burningand scaling themetal, and also greatly increasing the extent of heatingsurface.

3. I claim the mode of preventing the loss of power, otherwise caused bythe expansion of the air, liquid carbonic acid,or other driving power,in passing through the repository and refrigerator, and being cooled andcondensed before the working piston has completed its stroke, in themanner described-that is, by movingthe generating plunger downward, asthe working piston recedes from it; thus enlarging the heating chamberas fast as the air or other fluid expands. 1

4. I claim the combination of the gener- 'at-ing cylinders, with theopposite ends of the working cylinder direct; thus dispensing withcontracted passages and pipes, and causing the piston to move as rapidlyas the working fluid moves. i

5. I claim the construction of the heat repositories, and restorers, ofsmall glass tubes, or glass rods, arranged substantially as described,for the purposes specified.

6. I claim the combination of the heater, the repository, and thecooler, substantially as described, the heater being above the repository, and the cooler below it, so that as the heat rises, it doesnot tend to destroy the effect of the repository, but rather renders itmore perfect. a r

7 I claim thepartial isolation or separa tion, of the upper part of theouter case, containing the heating liquid, from the lower partcontaining the cooling liquid,by the introduction of bad conductingmaterial between them.

8. I claim the combination of the external heater, with the internalheater, and the combination of the external refrigerator, with theinternal refrigerator, substantially as specified, for the purposes setforth.

A. S. LYMAN.

Witnesses:

D. H. MEGIE, TIMOTHY D. JACKSON.

